Bobby agreed to be hypnotized during a comedy routine. While hypnotized, he stood on his chair and crowed like a rooster. Later, when his friends asked why he did this, Bobby replied that he didn't know, it must have been because he was hypnotized. What theory best explains his behavior?

The social-cognitive explanation of hypnosis best explains this behaviour.

Explanation:

The social-cognitive theory of hypnosis propose that the hypnotic experiences result from expectations of people who are motivated to take on the role of being hypnotized.

It is basically the theory that assumes that the people who are hypnotized are not in an altered state but are merely playing the role expected of them in the situation.

As in the given scenariom Bobby replied that he didn't know , the social-cognitive explanation of hypnosis best explains this behaviour.